Integrated circuits are made possible by processes which produce intricately patterned material layers on substrate surfaces. Producing patterned materials on a substrate requires controlled methods for deposition and removal of material layers. Modern semiconductor manufacturing processing applies increasing emphasis on the integration of films without air breaks between process steps. Such a requirement poses a challenge for equipment manufacturers to allow integration of various process chambers into a single tool.
One process that has become popular for deposition of thin films is atomic layer deposition (ALD). Atomic layer deposition is a method in which a substrate is exposed to a precursor which chemisorbs to the substrate surface followed by a reactant which reacts with the chemisorbed precursor. ALD processes are self-limiting and can provide molecular level control of film thicknesses. However, ALD processing can be time consuming due to the need to purge the reaction chamber between exposures to the precursors and reactants.
Selective deposition processes are becoming more frequently employed because of the need for patterning applications for semiconductors. Traditionally, patterning in the microelectronics industry has been accomplished using various lithography and etch processes. However, since lithography is becoming exponentially complex and expensive the use of selective deposition to deposit features is becoming much more attractive.
As device sizes continue to decrease to less than the 10 nm regime, traditional patterning processes using photolithography technology is becoming more challenging. Non-precise patterning and degraded device performance are more prevalent at lower device sizes. Additionally, the multiple patterning technologies also make fabrication processes complicated and more expensive.
Therefore, there is a need in the art for apparatus and methods to selectively deposit a film onto one surface selectively over a different surface.